Changes Of Maxillary Dentoalveolar And Dental Arch Produced By The Self-ligating System And Mbt Straight Wire During The Leveling And Aligning Phase Of Treatment

Objective:To evaluate changes in the maxillary dentoalveolar and dental arch produced by the self-ligating bracket and MBT bracket with mild crowding in the maxillary arch to level and align the maxillary dentition.Methods: dental casts of the maxillary were taken at immediately before treatment and at the end of leveling and aligning phase ,all dental casts were scanned by a special laser scanner and treated with geomagics software to install digital models,and tnen many landmarks of dentoalveolar and dental arch were selected in the digital models.all data were analyzed by SPSS17.0 software,and changes before and after treatment in dentoalveolar and the dentol arch widths, and shape of the maxillary arch were determined.Results:there are significant difference in anterior dentol arch widths and length with self-ligating and MBT bracket during before and the phase of aligning, and are no significance difference in dentoalveolar longth and widths, also there are significant increase in middle arch length of seli-ligating bracket ,but of MBT has not.Conclusion : aligned the maxillary dentition for the mild crowding patient,self-ligating bracket and tranditional MBT straight wire bracket can increase the arch widths and length in some degree,but there are no significant difference in two group.